JPH10229551A - Information supply controller and its method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To supply information efficiently. SOLUTION: In a cable modem 9, data supplied from a coaxial cable 8 to a LAN 10 are processed with the top priority. Data supplied from the coaxial cable 8 and returned to the coaxial able 8 are processed in the next priority order. Data inputted from the LAN 10 and outputted to the coaxial cable are processed in the 3rd priority order. Data supplied from the LAN 10 and returned to the LAN 10 are processed with the 4th priority.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information supply control apparatus and method, and more particularly, to an information supply control apparatus which can assign information to priorities and supply information efficiently. And methods.

[0002]

2. Description of the Related Art In a CATV (Cable Television) system, a video signal is distributed from a head end (broadcasting station) to a television receiver at a subscriber's home via an optical fiber cable or the like. Since the CATV system has a relatively large cable transmission capacity, it has been proposed to provide a connection service to the Internet. In this case, a cable modem is connected as a cable terminal, and a LAN (Local Area Network) using Ethernet (Ethernet) or the like is connected to the cable modem.
A plurality of personal computers and the like are connected via k). Each personal computer is connected to a LAN
And the headend further makes a connection to the Internet.

[0003]

However, if information is exchanged with the Internet using the CATV system as described above, the information is complicated, and in the worst case, each subscriber side has to perform real-time communication on the Internet. There is a possibility that the video signal distributed by the above cannot be received as a moving image. Further, when such a situation occurs, it takes a long time to return to a normal state.

[0004] The present invention has been made in view of such a situation, and aims to efficiently supply information.

[0005]

The information supply control device according to the present invention is characterized in that the received information includes first information provided from the first device to the second device and second information other than the first information. Determining means for deciding which of the above information, priority assigning means for giving priority to the first information over second information, and processing means for processing the information in accordance with the assigned priority And characterized in that:

In the information supply control method according to a third aspect, the received information is any one of the first information provided from the first device to the second device and the other second information. Determining a priority of the first information over the second information, and a processing step of processing the information in accordance with the assigned priority. And

In the information supply control device according to a fourth aspect, the received information is any one of the first information provided from the first device and the second information provided from the second device. Determining means for determining whether the first information has priority over the second information, and processing means for processing the information in accordance with the assigned priority. And

According to the information supply control method of the present invention, the received information is any one of the first information provided from the first device and the second information provided from the second device. Determining a priority of the first information over the second information, and a processing step of processing the information in accordance with the assigned priority. And

In the information supply control device according to the first aspect and the information supply control method according to the third aspect, the first information provided from the first device to the second device is the same as the other information. The processing is performed prior to the information of No. 2.

[0010] In the information supply control device according to the fourth aspect and the information supply control method according to the seventh aspect, the first information provided from the first device is the first information provided from the second device. 2 is processed prior to the information of item 2.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below. In order to clarify the correspondence between each means of the invention described in the claims and the following embodiments, each means is described. When the features of the present invention are described by adding the corresponding embodiment (however, an example) in parentheses after the parentheses, the result is as follows. However, of course, this description does not mean that each means is limited to those described.

In the information supply control device according to the first aspect, the received information is any one of the first information provided from the first device to the second device and the second information other than the first information. (E.g., step S3 in FIG. 9)
S4) and a ranking assigning means for giving a priority to give priority to the first information over the second information (for example, step S
5, S6) and processing means (for example, steps S21 to S33 in FIG. 10) for processing information in accordance with the assigned priority.

In the information supply control device according to the fourth aspect, the received information is any one of the first information provided from the first device and the second information provided from the second device. (E.g., step S in FIG. 9)
3) and an order assigning means for assigning a priority in which the first information is prioritized over the second information (for example, step S5 in FIG.
S6, S8, S9) and processing means for processing information corresponding to the assigned priority (for example, step S in FIG. 10)
21 to S33).

FIG. 1 shows a configuration example of a CATV system to which the information supply control device of the present invention is applied. In this system, a center 1-1 as a broadcasting station (video provider) has a head end 21 that provides video information to be broadcast and performs a process of transmitting and receiving information.
A converter 5 is connected to the center 1-1 via a coaxial cable 4. The converter 5 converts an electric signal input through the coaxial cable 4 into an optical signal and outputs the optical signal to the optical fiber cable 6, and converts the optical signal input from the optical fiber cable 6 into an electric signal. , And output to the coaxial cable 4. Similarly, the converter 7
Converts the optical signal input from the optical fiber cable 6 into an electric signal and outputs the electric signal to the coaxial cable 8,
The electronic signal input from the coaxial cable 8 is converted into an optical signal and output to the optical fiber cable 6.

That is, in this system, HF
A C (Hybrid Fiber Coax) system is adopted, and the optical fiber cable 6 extends to the vicinity of the cable modem 9 (for example, within a range of several hundred meters).
Information is transmitted through the coaxial cable 8.

The cable modem 9 is further connected to a LAN 10 using Ethernet or the like. And
Terminals 11-1 to 11-n are connected to the LAN 10, and the terminals 11-1 to 11-n respectively
Personal computers (PC) 12-1 to 12-
n, home terminals 13-1 to 13-n, and television receivers (TVs) 14-1 to 14-n.

An Internet 2 is connected to the center 1-1, and computers 3-1 and 3-2 are connected to the Internet 2 in addition to another center 1-2.

FIG. 2 shows a configuration example of the cable modem 9. MAC (Media Access Control) filter 31
Receives input of data (downstream) from the center 1-1 supplied from the converter 7 via the coaxial cable 8, and extracts only data having a destination address (MAC address) addressed to itself from the data. And
DHCP (Dynamic Host Configuration Protocol) / DNS (Domain
Naming System) / SNMP (Simple Network Mangement Prot)
ocol) unit 32 and an IP (Internet Protocol) filter / T
Output to a TL (Time To Live) filter 33. The ARP (A
ddress Resolution Protocol), and devices that are connected adjacently (headend 21,
The terminal 11-1 to 11-n) and its own MAC address are set in advance.

The DHCP / DNS / SNMP unit 32 has its DHCP
The (dynamic host configuration protocol) section executes a process of dynamically allocating an IP address. Further, the DNS unit performs a process of replacing a domain name with an IP address so that a computer registered in the Internet 2 can be uniquely identified by a name.

A function of performing substantially the same processing as that of the DHCP unit and the DNS unit is provided in the head end 21. The assignment of the IP address to the terminals 11-1 to 11-n is performed by the head end 21. It is performed by
The DHCP unit and the DNS unit of the cable modem 9 function auxiliary when the connection between the cable modem 9 and the head end 21 is released for some reason.

The SNMP (Simple Network Management Protocol) unit of the cable modem 9 manages and monitors nodes in the network. Specifically, for example, processing of a response to a status inquiry from the head end 21 is performed.

The IP of the IP filter / TTL filter 33
The filter unit includes a terminal 11-of the LAN 10 (Ethernet side) among the data supplied from the MAC filter 31.
Only the data having the destination IP address assigned to 1 to 11-n is extracted. TTL
The filter 33 determines whether or not the input data packet is of a time that can last on the Internet 2 (a value of TTL is 2 or more), and extracts only data that can still exist, The TTL value is decremented by 1 and output. The data extracted by the IP filter / TTL filter 33 is DHCP / DNS / SNMP.
And a MAC address adding unit 34.
The MAC address adding unit 34 adds a MAC address to data supplied from the DHCP / DNS / SNMP unit 32 or the IP filter / TTL filter 33, and outputs the data to the LAN 10.

The MAC filter 35 extracts only data having a destination address (MAC address) addressed to the cable modem 9 from the data supplied from the LAN 10, and outputs the data to the DHCP / DNS / SNMP unit 32 and the IP filter / TTL filter. 36. IP filter / TT
The L filter 36 includes terminals 11-1 to 11-1 to be managed.
1-n, and extracts only data of a packet that can still exist on the Internet and has a MAC address adding unit 37 and a DHCP / DNS / SNMP unit 32.
Output to The MAC address adding unit 37 adds a MAC address to data supplied from the IP filter / TTL filter 36 or the DHCP / DNS / SNMP unit 32, and outputs the data to the coaxial cable 8 as an upstream.

DHCP / DNS / SNMP unit 32, IP filter / T
The TL filter 33 and the IP filter / TTL filter 36 include buffer memories 32A and 3 for storing data.
3A or 36A, respectively.

FIG. 3 shows the head end 21 of the center 1-1.
And the spectrum of the signal between the terminals 11-1 to 11-n. As shown in the figure, a frequency band of 10 MHz to 55 MHz is used for upstream, that is, transmission from the terminals 11-1 to 11-n to the center 1-1, and a frequency band of 70 MHz to 750 MHz is used for downstream, That is, it is used to transfer data from the center 1-1 to the terminals 11-1 to 11-n. The frequency band for the downstream is set wider than the frequency band for the upstream. This means that from the center 1-1 to the terminals 11-1 to 11-n,
While the video data is transmitted, a wide band is required, whereas the upstream data is transmitted because the command is mainly used and a narrow band may be used. In the frequency band for the downstream, one channel is allocated to a width of 6 MHz. Since the cable modem 9 requires n channels, n channels are reserved for each of the upstream and the downstream. The n channels (hereinafter, appropriately referred to as modem channels assigned to the cable modem 9) are mainly channels used between the head end 21 and the home terminal 13 for television broadcasting (hereinafter, appropriately referred to as broadcast channels). Channels) are channels of different frequency bands.

FIG. 4 shows a frame format of a downstream modem channel. As shown in FIG.
A synchronization signal (SYNC) having a value of 7H is arranged. Next to this, a value N indicating the presence or absence of a subsequent frame is arranged. This value N is set to 187 when there is a subsequent frame, and when there is no subsequent frame (when it is the last frame), the number of bytes of the following payload is described. That is, a 186-byte payload is arranged next to the value N. If, for example, 50-byte data is recorded in this payload, N = 50. The payload is followed by a 16-byte FEC (Forward Error Correction) for error detection. On the receiving side, error detection and correction processing is performed using this FEC.

FIG. 5 shows the frame format of the upstream modem channel. As shown in the figure, a guard time for absorbing jitter and a preamble for generating a clock are arranged before an upstream frame. After the preamble, a 1-byte synchronization signal having a value of 47H is arranged. Following the synchronization signal, a value S is arranged. After the value S, a 120-byte payload is arranged. The value S is set to S = 121 when this frame is not the last frame, and is set to the same value as the number of bytes of the payload when this frame is the last frame, similarly to the value N in FIG. Following the payload, a 6-byte FEC is arranged.

FIG. 6 shows the relationship between the frame configurations of the cable modem 9 and the Ethernet modem channel. As shown in the figure, in the cable modem 9, a data unit is an IP datagram. In this IP datagram, the IP header
(header) is placed, followed by TCP (Transmission Co
ntrol Protocol) header, followed by application data. The TCP header and the application data constitute a TCP segment. The application data includes an application header and user data.

The IP header is 20 bytes, the TCP header is 20 bytes, and the sum of these and application data (IP datagram) is 46 to 15 bytes.
00 bytes.

14 before the IP header of the IP datagram
A 4-byte Ethernet header is added, and a 4-byte Ethernet trailer (trade) follows the application data.
iler) is added to form an Ethernet frame.

As shown in FIG. 7, the Ethernet header has a destination address (destinati) of 6 bytes.
on address), 6-byte source address (source addre
ss) and a 2-byte type. The destination address indicates an address of a data transmission destination, and the source address indicates an address of a data transmission source. The type indicates the type of data.

FIG. 8 shows the structure of the IP header.
At the top is a 4-bit version, followed by a 4-bit header length, followed by an 8-bit TOS (Type of Service).
Is arranged.

Next, a 16-bit total length is arranged.
A bit ID (identification) is arranged.

Following the ID, a 3-bit flag (flags)
And 13-bit fragment offset (flagment offs
et), respectively. And then,
An 8-bit TTL and a protocol are arranged. Following the protocol is a 16-bit header checksum (hea
der checksum), followed by a 32-bit source IP address and a destination IP address.

Next, the basic operation of the cable modem 9 will be described.
It is assumed that a C address and an IP address are allocated.

For example, when the home terminal 13-1 of the terminal 11-1 is operated to receive a television broadcast signal of a predetermined channel, the converter 5, the converter 7, the cable modem 9. From the broadcast channel signals input via the LAN 10, the home terminal 13-1 receives the commanded channel signal and outputs it to the television receiver 14-1 for display. In this way, a broadcast program corresponding to the command can be viewed. The processing in this case is the same as the processing in the conventional CATV system.

Next, processing of data of a modem channel will be described.

For example, when the personal computer 12-1 of the terminal 11-1 instructs the computer 3-1 to access the home page, the personal computer 12-1 sets the destination IP address shown in FIG.
1 is specified, and the IP address of the personal computer 12-1 is specified as the source IP address. The MAC address ab: cd: aa: 44: 33: 11 of the cable modem 9 is specified as the destination address of the Ethernet header shown in FIG. 7, and the MAC address 34:17 of the personal computer 12-1 is specified as the source address. : Af: 2
8:33:11 is specified.

MAC filter 35 of cable modem 9
Extracts the data because the destination address of the Ethernet header is its own MAC address, and supplies it to the IP filter / TTL filter 36. The IP filter / TTL filter 36 determines whether or not the source IP address included in the IP header in the input data belongs to the device to be managed, and determines the duration of the data on the Internet. , It is determined whether or not it has expired. When both conditions are satisfied, the IP filter / TTL filter 36 outputs the data (I
P datagram) to the MAC address adding unit 37.

The MAC address adding unit 37 converts the data (IP datagram) supplied from the IP filter / TTL filter 36 into the MAC address ff: ff: ff: ff: ff: of the head end 21 as the destination address of the Ethernet header. ff: 01 as its source MAC address ab: cd: a
a: 44: 33: 11, respectively, and the coaxial cable 8 to the optical fiber cable 6 as upstream.
Output to

The headend 21 of the center 1-1 outputs data transmitted via the optical fiber cable 6 to the computer 3-1 via the Internet 2. As described above, the computer 3-1 outputs the homepage data to the head end 21 of the center 1-1 via the Internet 2 when the access is made from the personal computer 12-1. At this time, the source IP address is the I-
The P address is 312.0.0.1, and the destination IP address is the personal computer 12-1.
Is set to 192.0.0.1. The source address of the Ethernet header is the computer 3
-1 MAC address 55: 39: de: 71: 33:
55, and the destination address is the MAC address ff: ff: ff: ff: ff: f of the head end 21.
f: 01 is set.

The head end 21 is connected to the computer 3-1.
The data supplied from is converted into an Ethernet frame.
Then, the destination address of the Ethernet header is changed to the MAC address ab of the cable modem 9:
cd: aa: 44: 33: 11, and the source address is the MAC address ff: ff: ff: of the head end 21.
ff: ff: 01 is output to the cable modem 9.

The cable modem 9 sets the destination address of the Ethernet header to the MAC address 34: 17: af: 2 of the personal computer 12-1.
8:33:11 and change the source address to its own MAC address ab: cd: aa: 44: 33: 11
And outputs the data to the personal computer 12-1 via the LAN 10.

On the other hand, the cable modem 9 is connected, for example, from the personal computer 12-1 of the terminal 11-1 to the terminal 1
When data to be transmitted is input to the 1-n personal computer 12-n, the following operation is performed. As the destination address of the Ethernet header, the MAC address a of the cable modem 9 is used.
b: cd: aa: 44: 33: 11 is set as the source address, and the MAC address 34: 17: af: 28: 33: 11 of the personal computer 12-1 is set. The destination IP address of the IP header is the personal computer 1
2-n IP address 199.0.0.1 is the source I
As the P address, the personal computer 12-1
Are set, respectively.

The MAC filter 35 of the cable modem 9
When the data is input from the personal computer 12-1 via the LAN 10, it determines from the Ethernet header whether or not the data has a destination address addressed to itself. In this case, since the data has the destination address addressed to itself, this data (IP datagram) is
Output to the TTL filter 36.

The IP filter / TTL filter 36 checks the IP address and TTL in the input data, and if they are correct, the IP datagram
This is supplied to the NS / SNMP unit 32. The DHCP / DNS / SNMP unit 32 converts the input IP datagram into a MAC address
4 The MAC address adding unit 34 is configured by DHCP / DNS
In the data (IP datagram) supplied from the / SNMP unit 32, the MAC address 34: 17: af: 28: 33: 99 of the personal computer 12-n is set as the destination address of the Ethernet header, and the own address is set as the source address. MAC address ab: cd:
aa: 44: 33: 11 are set respectively, and LAN1 is set.
Output to 0.

The LAN 10 transmits this data to each terminal 11
-1 to 11-n. Among the terminals, the terminal 11
Since the -n personal computer 12-n is specified by the destination address of the Ethernet header and the destination IP address of the IP header, the data is fetched and processed.

When a predetermined command (for example, a command requesting to return the status) is input from the headend 21 and a response (status) corresponding to the command is returned, the cable modem 9 operates as follows. I do. That is,
The MAC filter 31 extracts the Ethernet header of the data supplied from the head end 21, and extracts the destination address written therein. When the destination address is its own MAC address, the IP filter / TTL filter 33
But, furthermore, its destination IP address is
It is determined whether it is addressed to itself. When the IP address is addressed to itself, the data (IP datagram) is supplied to the DHCP / DNS / SNMP unit 32.

The DHCP / DNS / SNMP unit 32 extracts the application data of the IP datagram in the input Ethernet frame. Then, the SNMP unit performs a process corresponding to the command included therein. The SNMP unit generates a response corresponding to the command and writes the response to the application data in the IP datagram. The DHCP / DNS / SNMP unit 32 writes the IP address 11.0.0.1 of the cable modem 9 as the source IP address of the IP header, and writes the IP address 10.0 of the headend 21 as the destination IP address. Write 0.1. Then, the IP datagram is output to the MAC address adding unit 37.

[0050] The MAC address adding section 37 is provided for the MAC address ff: ff: ff: ff: ff: f of the head end 21.
f: 01 is the destination address, and the MAC address of the cable modem 9 itself is ab: cd: aa: 4
4:33:11 is set as the source address in the Ethernet header. The MAC address adding unit 37 outputs this data to the coaxial cable 8.

As described above, the processing of the modem channel of the cable modem 9 includes the processing of outputting data supplied from the coaxial cable 8 to the LAN 10 and the processing of data corresponding to the data input via the coaxial cable 8. 8, a process of outputting data supplied from the LAN 10 to the coaxial cable 8, a process of outputting data supplied from the LAN 10 to the LAN 10 again,
There are four processes. DHCP / DNS for cable modem 9
The / SNMP unit 32 adds priorities to these four processes. FIG. 9 shows an example of processing for adding the priority.

First, in step S1, it is determined whether or not the input data is data having a destination address (MAC address) addressed to the cable modem 9. This determination is made by the MAC filters 31 and 35 from the destination address of the Ethernet header. If it is determined that the input data is not data having a destination address addressed to the cable modem 9, the process proceeds to step S2, where a discard process is performed. That is, in this case, the cable modem 9 does not perform any special processing.

If it is determined in step S1 that the input data is data having a destination address addressed to itself, the process proceeds to step S3.
It is determined whether the input data is data from the Ethernet (LAN 10) side. This judgment is based on MA
The C filters 31 and 35 determine from the source address of the Ethernet header. Or IP filter /
The TTL filters 33 and 36 determine from the source IP address in the IP header.

In step S3, when it is determined that the input data is not data from the Ethernet (LAN 10), that is, the data is supplied from the center 1-1 via the coaxial cable 8. If it is determined, the process proceeds to step S4, and it is determined whether or not the data is data for the cable modem 9 itself. This determination is based on the IP filter / TTL filter 3
According to 3,36, the destination IP of the IP header
Done from address. If it is determined in step S4 that the input data is not data for the cable modem 9 itself, the process proceeds to step S5, where the DHCP / D
The NS / SNMP unit 32 sets the priority of the input data to A. Destination IP of input data
If it is determined in step S4 that the address is set in the cable modem 9, the process proceeds to step S6,
The DHCP / DNS / SNMP unit 32 sets the priority for the data as B.

Further, if it is determined in step S3 that the input data is data from the LAN 10, the process proceeds to step S7, and the transmission destination of the data is
It is determined whether it is on the Ethernet side. This determination is made by the IP filter / TTL filters 33 and 36.
This is performed by reading the destination IP address of the IP header.

If it is determined in step S7 that the input data is not data to be transmitted to the LAN 10 side, that is, if it is determined that the input data is data to be transmitted to the coaxial cable 8 side, the process proceeds to step S8, where the DHCP / DNS / S
The NMP unit 32 assigns C to the data as priority.
Set. If it is determined in step S7 that the input data is data to the LAN 10, the process proceeds to step S9, and the DHCP / DNS / SNMP unit 32 sets D as a priority.

In the set order, the priority becomes higher in the order of A, B, C, and D. Therefore, the data having the highest priority is data input through the coaxial cable 8 and output to the LAN 10. This data is transmitted, for example, from the computer 3-1 to the Internet 2 and the headend 2
1 is the image data supplied to the personal computer 12-1 via the PC 1, the data amount is the largest, and this data may be moving image data. If this data is missing, the moving image cannot be displayed. Therefore, processing is performed with the highest priority.

On the other hand, since the data of the priority order B is data addressed to the cable modem 9 itself, it is usually a command to the cable modem 9 in many cases. Since the response corresponding to this command can be appropriately performed after the processing of the data having the priority A is completed,
The priority is set lower than the data having the priority A.

On the other hand, in the data supplied from the LAN 10, the data output to the coaxial cable 8 is given priority C and is processed with priority compared to the data returned to the LAN 10 which is given priority D. Data output from the cable modem 9 to the coaxial cable 8 can often be processed only by the cable modem 9. On the other hand, the process of returning to the LAN 10
If another cable modem is present, that cable modem can handle it. For this reason, data output to the coaxial cable 8 is processed with priority over data returned to the LAN 10.

Further, in the case of this embodiment, the cable modem 9 performs the processing of the data supplied from the coaxial cable 8 in preference to the data supplied from the LAN 10. That is, the LAN is a network used in a relatively narrow range, whereas the coaxial cable 8
Since the network connected to the side is a network including a wider range as represented by the Internet 2, it is determined that the urgency is higher.

FIG. 10 shows specific processing in the DHCP / DNS / SNMP unit 32 and the IP filters / TTL filters 33 and 36 when the priorities are set as described above. That is, first, in step S21, it is determined whether data of the priority order A is being processed. If the data having the priority A is being processed, the process proceeds to step S22, where the data having the priority B, C or D (data having a low priority) is stored in the buffer memories 32A and 32A.
3A or 36A, respectively. Next, the process proceeds to step S23, where these memories 32A, 33A, 36
It is determined whether or not A overflows. If it is determined that A does not overflow, the process returns to step S21, and the subsequent processing is repeatedly executed. On the other hand, in step S23, the memories 32A, 33A,
When it is determined that 36A overflows, the process proceeds to step S24, and a process of discarding the overflowed data as it is is performed. Then, the process returns to step S21.

In this way, the processing of the priority A is executed even at the expense of data having a lower priority.

If it is determined in step S21 that the data of the priority A is not being processed, the process proceeds to step S2.
Then, it is determined whether or not data of the priority B having the next highest priority is being processed. When it is determined that the data of the priority B is being processed, the process proceeds to step S26, and the process of storing the data of the lower priority C and the data of the priority D in the memories 32A, 33A, and 36A is executed. . In step S27, the memories 32A, 33
It is determined whether or not A, 36A overflows. If it is determined that overflow does not occur, step S25 is performed.
And the subsequent processing is repeatedly executed. In step S27, the memories 32A, 33A, 36A
If it is determined that the data of the priority order C or D overflows, the process proceeds to step S28, and the overflowed data is discarded as it is. Thereafter, the process returns to step S25, and the subsequent processes are repeatedly executed.

That is, in this way, the data of the priority B is executed preferentially even at the expense of the data of the lower priority C and D.

If it is determined in step S25 that the data of the priority order B is not being processed, the process proceeds to step S2
The process proceeds to step S9, and it is determined whether data of the priority order C is being processed. If it is determined that the data of the priority C is being processed, the process proceeds to step S30, where the priority is low.
A process of writing the data of the priority order D into the memories 32A, 33A, 36A is executed. Then, in step S31, it is determined whether or not the data of the priority order D overflows in the memories 32A, 33A, and 36A. If it is determined that the data does not overflow, the process returns to step S29, and the subsequent processing is repeated. Be executed. In step S31, if the data of the priority order D overflows, if it is determined in step S31, the process proceeds to step S32, and a process of discarding the overflowed data as it is is executed. Thereafter, the process returns to step S29, and the subsequent processes are repeatedly executed.

Thus, the data of the priority order C is
Even at the expense of lower priority D data, the process is performed.

If it is determined in step S29 that the data of the priority C is not being processed, the process proceeds to step S33, and the processing of the data of the priority D having the lowest priority is executed.

In the above embodiment, the LAN 10
In the above, Ethernet is used, but other formats can be used.

[0069]

As described above, according to the information supply control apparatus according to the first aspect and the information supply control method according to the third aspect, the first apparatus provided from the first apparatus to the second apparatus. Since the information is processed prior to the other second information, the information can be efficiently supplied.

Similarly, according to the information supply control device according to the fourth aspect and the information supply control method according to the seventh aspect,
Since the first information provided from the first device is processed prior to the second information provided from the second device, information can be efficiently supplied.

[Brief description of the drawings]

FIG. 1 is a CATV to which the information supply control device of the present invention is applied.
FIG. 1 is a block diagram illustrating a configuration example of a system.

FIG. 2 is a block diagram illustrating a configuration example of a cable modem in FIG. 1;

FIG. 3 is a diagram showing a spectrum of a transmission signal on the optical fiber cable of FIG. 1;

FIG. 4 is a diagram illustrating a downstream frame format in the CATV system of FIG. 1;

FIG. 5 is a diagram illustrating an upstream frame format in the CATV system of FIG. 1;

FIG. 6 is a diagram illustrating a relationship between an Ethernet frame and an IP datagram.

FIG. 7 is a diagram illustrating an Ethernet header.

FIG. 8 is a diagram illustrating an IP header.

FIG. 9 is a flowchart illustrating a process of setting a priority order.

FIG. 10 is a flowchart illustrating processing of data for which the order is set.

[Explanation of symbols]

1-1, 1-2 center, 2 Internet, 3
-1,3-2 computer, 4 coaxial cable,
5 converter, 6 optical fiber cable, 7 converter,
8 coaxial cable, 9 cable modem, 10
LAN, 11-1 to 11-n terminals, 12-1 to 12-n personal computers, 13-1 to 13-n home terminals, 14-1 to 14-n
Television receiver, 21 head end, 31
MAC filter, 32 DHCP / DNS / SNMP section, 33
IP filter / TTL filter, 34 MAC address adding unit, 35 MAC filter, 36 IP filter / TTL filter, 37 MAC address adding unit

Claims (7)

[Claims] A first device connected to the first device via a cable and connected to a plurality of second devices via a network, wherein the first device and the plurality of second devices are connected to the first device; An information supply control device that controls the supply of information output by the device, wherein the received information is one of first information provided from the first device to the second device and second information other than the first information. Determining means for determining whether the first information is higher than the second information; and ranking processing means for processing the information in accordance with the assigned priority. An information supply control device comprising: 2. The information supply control device according to claim 1, wherein the determining unit determines that the received information is information addressed to itself, as the second information. 3. The first device and the plurality of second devices are connected to the first device via a cable, and are connected to a plurality of second devices via a network. In the information supply control method for controlling the supply of the information output by the first device, the received information may be any one of the first information provided from the first device to the second device and the second information other than the first information. A determining step of determining whether the first information is higher than the second information; and a processing step of processing the information in accordance with the assigned priority. An information supply control method comprising: 4. The first device and the plurality of second devices are connected to the first device via a cable and connected to a plurality of second devices via a network. An information supply control device that controls supply of information output by the device, wherein the received information is any one of the first information provided from the first device and the second information provided from the second device. Determining means for determining whether the first information is higher than the second information; and ranking processing means for processing the information in accordance with the assigned priority. An information supply control device comprising: 5. The determination unit further determines whether the second information is third information to the first device or fourth information to another second device. 5. The information supply control device according to claim 4, wherein the order assigning unit assigns the third information with a priority that is higher than the fourth information. 6. The determination means further determines whether the first information is the third information to the second device or the fourth information addressed to itself, and The information supply control device according to claim 4, wherein the means gives the third information a priority that is higher than the fourth information. 7. The first device and a plurality of the second devices, which are connected to the first device via a cable and connected to a plurality of second devices via a network. In the information supply control method for controlling the supply of the information output by the device, the received information may be any one of the first information provided from the first device and the second information provided from the second device. A determining step of determining whether the first information is higher than the second information; and a processing step of processing the information in accordance with the assigned priority. An information supply control method comprising: